Treatment of textile materials



Patented Feb. 19, 1952 TREATMENT OF TEXTILE MATERIALS George E. Niles, Winchester, Masa, assignor to Monsanto Chemical Company, St.

corporation of Delaware No Drawing. Application August 27, 1947, Serial No. 770,943

- 6 Claims. 1

This invention relates to improved textile finishing materials, and methods of treating yarns and fabrics therewith.

It is common practice to treat yarns and fabrics with starch solutions in order to impart a relatively stiffened finish thereto. Starched fabrics however lose their stiffened character and appearance after asingle washing, and also tend ,to dust out. Furthermore, fabrics treated with starch finishes will not retain the stifiened finish after mild washing.

It is the primary object of the present invention to provide a substantially permanent stiffened finish which cannot be appreciably removed by ordinary washing operations and is substantially free of dusting.

Still further objects and advantages of the invention will appear from the following description and appended claims.

In accomplishing the above objects the yarns or fabric is treated, as by dipping or spraying.

with an aqueous solution or dispersion of an alkali or amine salt, including sodium, potassium, ammonium and quaternary ammonium salts of copolymerized styrene-maleic anhydride, after which the yarn is treated with a dilute solution of a heavy metal salt. The treated fabric is then dried, whereby an insoluble salt of the copolymer is formed, which remains on the fabric after washing and provides a substantially permanent finish.

The concentration of the styrene-maleic salt solution and the pick-up should be adjusted to deposit on the fabric from 2 to 15% by weight of the styrene-maleic salt, but preferably between about 4 and 7%. The heavy metal salt solution employed is generally dilute, as only small sections of cloth are subjected to this solution at any one time. Moreover, the time of immersion of the cloth in the solution may be varied in accordance with the concentration. In general, solutions of about 1 to 2% strength are used, but stronger solutions may be employed, if desired.

It the heavy metal salt is water-soluble, it may be applied to the fabric before the salt of the anhydride is applied, or after the salt of the anhydride is applied but before drying, or it may be applied after the salt of the anhydride is applied and dried. However, in cases in which the heavy metal salt is insoluble in water, these salts are first dispersed in the aqueous bath of the salt of the anhydride before being applied. Fabrics treated with these combined dispersions are then dried to form the insoluble heavy metal salt of the anhydride.

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The heavy metal salts which may be used for the purpose of this invention are salts of aluminum, antimony, arsenic, barium, beryllium. bismuth, cadmium, calcium, cerium, cesium, chromium, cobalt, copper, iron, lead, magnesium, manganese, mercury, molybdenum, nickel, platinum, silver, strontium, tin, zinc and zirconium. Suitable ammonium or amine salts of the copolymer include the salts of ammonia, guanidine, alkylamines, such as methyl, butyl and amyl amine, and quaternary ammonium hydroxides, such as phenyl trimethyl ammonium hydroxide.

The copolymer of styrene and maleic anhydride used in accordance with this invention is a wellestablished product which may be prepared in several ways. One of the well-known methods is mass polymerization, which involves heating styrene and maleic anhydride at temperatures between about 100 and 300 F. for several hours or more. Preferably, the materials are heated cautiously, as in a water bath. Another method which may be used is known as the solvent process which involves reacting the styrene and maleic anhydride at slightly elevated temperatures in the presence of a solvent which is capable of dissolving both the starting materials and the finished polymer, such as acetone. If desired, the copolymerization may be carried out in the presence of a catalyst, such as benzoyl peroxide. Still another method which can be used is the solvent-non-solvent method which involves carrying out the reaction as above, but in a solvent which is capable of dissolving only the starting material and not the final copolymer.

The copolymer of styrene and maleic anhydride produced by the above or by any other wellknown method of manufacture is soluble in acetone, but insoluble in alcohol or benzene, and forms water-soluble salts of ammonia or alkali metals. Instead of styrene, substituted styrenes, such as methyl or butyl styrene, chlorstyrene or the like, may be used to prepare copolymers which are soluble in dilute aqueous solutions of alkali or ammonia. Instead of maleic anhydride, partially esterifled maleic anhydride, such as the half ester of isopropyl maleate, may be used. It

is also possible to prepare and use in accordance with this invetnion copolymers of styrene and maleic anhydride which have been copolymerized with relatively small amounts of other unsaturated compounds, such as vinyl acetate, vinyl chloride, vinyl ethyl ether, indene, vinyl methyl ketone, acrylic esters and the like.

A further understanding or the mvenuoa will be obtained from the following examples, the parts being given by weight:

Example I A solution of an ammonium salt of styrenemaleic anhydride resin was prepared by mixing together 600 parts of styrene-maleic anhydride, prepared by copolymerizing equimoleeular quantitles of styrene and maleic anhydride at about 200 F. in a water bath, 400 parts of 28% NHAOH and 9000 parts of water. The resulting mixture was then heated to 200 to 212 F. with stirring, and maintained at this temperature until a uniform, somewhat viscous transparent solution resulted. This required about one hour.

Spun rayon fabric and heavy cotton sheeting were dipped in the bath prepared as described above, after which it was passed through a padder adjusted for 100% pick-up. The: bath was maintained at about 120 F. during the treatment to insure uniform penetration. The treated sheeting was then dried, after which the dried sheeting was immersed in a 2% zirconium oxychloride solution for minutes at 120 F. Following this the treated fabric was thoroughly rinsed and dried. The finished fabric was resistant to washing and showed good water-repellency.

Example II Samples of spun rayon fabric and cotton fabric treated with ammonium salt solutions prepared as described in Example I were treated with 1% solutions of aluminum formate, copper acetate and antimony chloride respectively for 10 minutes at 120. The fabrics were then thoroughly rinsed and dried. The treated fabrics had a full firm hand and were resistant to washing.

Example I II On thousand parts of a 7% aqueous solution of the ammonium salt of the copolymer of styrene and maleic anhydride were mixed with parts of powdered CaCO: and ball milled for 24 hours. Samples of spun rayon and cotton sheeting were immersed in the dispersion thus prepared and then padded, the pad being adjusted to deposit on the fabric 7 solids. The treated fabrics were then dried at 200 F. for 5 minutes and cured for 5 minutes at 280 F. The resulting fabrics were resistant to washing and had a stifi finish.

Although the examples refer to the treatment of cotton and viscose fabrics, the process is also applicable to acetate rayon, nylon, glass, linen, fiax, hemp, jute, ramie, wool, silk, cuprammonium rayon and synthetic protein fabrics, and fabrics containing mixtures and blends of any of the above materials.

By treating fabrics with the finishing agents described herein, a substantially permanent, stiffened finish is obtained, due to the fact that only relatively small amounts of the dried and reacted resin are lost on washing, 1. e. of the order of 2 to 10%. The finished fabric is also smooth and substantially free of dusting in contrast to the well-known starch treated fabrics. When the resin is applied to the warp yarn and insolubilized thereon, there is the further advantage that the weaving operation is improved owing to the higher tensile strength of the yarn, its increased resistance to abrasion, and its generally stiffened character. The fabric prepared from treated yarn has the desired finish characteristics without further treatment, but if desired it may be subjected to additional finishing operations. The styrene-maleic salt may also be applied to the yarn without insolubilization, after which the yarn is woven, and the heavy metal salt solution is applied.

It is customary to apply the sizing or finishing materials described herein to yarns or fabrics. However, it is possible to obtain similar results by treating fibers, either initially or at any stage of their processing prior to spinning, after which the fibers may be spun and woven to obtain fabrics of the desired finish characteristics. Yarns prepared from such treated fibers may also be readily woven. It is also possible to treat in accordance with this invention fibers which are to be used as such, as for example in cotton batting, or in the preparation of non-woven fabrics.

It is believed that the insolubility, resistance to washing and water-repellency of fabrics treated according to this invention are due to the metathesis of the heavy metal ion for the ammonium or alkali ion in the salt of the styrenemaleic anhydride copolymer. This exchange may take place before, during or after the drying operation.

It should be understood that the aqueous solutions referred to in the appended claims are intended to include acqueous dispersions, as it is possible that the ammonium or amine salts, in the solution are actually present in the form of a colloidal dispersion.

What is claimed is:

1. The method of preparing and finishing textile fabrics which comprises treating yarns with an aqueous solution of a salt of copolymerized styrene-maleic anhydride selected from the group consisting of alkali salts and amine salts, said solution being supplied in an amount sufficient to provide from 4 to 7% by weight of the salt based on the yarn weaving the resulting yarns into fabrics, then applying an aqueous solution of a heavy metal salt to the fabric, after which the fabric is dried.

2. The method of preparing and finishing textile fabrics which comprises treating yarns with an aqueous solution of a salt of a copolymer prepared by copolymerizing a substance selected from the group consisting of styrene, methyl styrene, butyl styrene and chlorostyrene with a substance selected from the group consisting of maleic anhydride and partial esters of maleic acid. said salt being selected from the group consisting of alkali salts and amine salts, said solution being supplied in an amount sufficient to provide from 4 to 7% by weight of the salt, based on the yarn, weaving the resulting yarns into fabrics, then applying an aqueous solution of a heavy metal salt to the fabric, after which the fabric is dried.

3. The method according to claim 1, but further characterized in that the heavy metal salt is a zirconium salt.

4. The method according to claim 1, but further characterized in that the heavy metal salt is an aluminum salt.

5. The method according to claim 1, but further characterized in that the heavy metal salt is a copper salt.

6. The method of preparing and finishin textile fabrics which comprises treating yarns with an aqueous solution of an ammonium salt of copolymerized styrene-maleic anhydride, said solution being supplied in an amount sufficient to provide from 4 to 7% by weight of the salt based on the yarn, weaving the resulting yarns into 15 fabrics; then applying an aqueous solution of a heavy metal salt to the fabr1c, after which the UNITED STATES PATENTS fab! is dried- Number Name Date GEORGE NILES- 1,976,679 Fikentscher et a1. Oct. 9, 1994 l 2,319,852 Doolittle May 28, 1943 REFERENCES CITED 2,356,879 Pense et a1 Aug. 29, 1944 The following references are of record in the file of this patent: 

1. THE METHOD OF PREPARING AND FINISHING TEXTILE FABRIC WHICH COMPRISES TREATING YARNS WITH AN AQUEOUS SOLUTION OF A SALT OF COPOLYMERIZED STYRENE-MALEIC ANHYDRIDE SELECTED FROM THE GROUP CONSISTING OF ALKALI SALTS AND AMINE SALTS, SAID SOLUTION BEING SUPPLIED IN AN AMOUNT SUFFI CIENT TO PROVIDE FROM 4 TO 7% BY WEIGHT OF THE SALT BASED ON THE YARN WEAVING THE RESULTING YARNS INTO FABRICS, THEN APPLYING AN AQUEOUS SOLUTION OF A HEAVY METAL SALT TO THE FABRIC, AFTER WHICH THE FABRIC IS DRIED. 